NEW YORK 
They frolic in empty boxes and stick their heads under faucet streams of water. They dance on tippy toes and fly through the air with Pop-Tarts. They play piano wearing little frocks and get tickled to distraction to the delight of millions on YouTube.

I speak, of course, of the cat stars of the Internet, a place filled with felines and their wacky uploading humans since the dawn of bandwidth. Now, after years of viral viewing, they’re coming into their own in lucrative and altruistic ways.

The first Internet Cat Video Film Festival drew a Woodstock-esque crowd of more than 10,000 — people, that is — to a Minneapolis art museum in August. Police closed a span of highway clogged with cars trying to get to the Walker Art Center for the free outdoor slate of 80 videos culled from 10,000 submissions that spanned from a simple, funny moment to polished animations.

“People were spilling out into the streets. It kind of took our breath away,” said the museum’s Scott Stulen, who worked on the festival and helped curate entries.

Corporate kittydom is happy with the higher profile for the cat meme, which actually goes back to the 1970s, when swapping VHS tapes was big and the word meme was barely known. It means, by the way, all the crazy, viral themes that spread online faster than you can say nom, nom, nom (cat-vid speak for the sound of a cat eating.)

In addition to the Walker’s free night in cat video heaven, Fresh Step litter sponsored Catdance, an evening of felines on screen that coincided with January’s Sundance Film Festival in Park City, Utah. A fan-voted winner among five scripted finalists will earn $10,000 after online voting ends later this month.

In November, Friskies gave a lifetime achievement statue to angsty existentialist Henri, le Chat Noir, at the brand’s own awards ceremony and donated 250,000 cans of cat food to shelters around the country.

Roly poly Maru, the megastar in Japan with millions of views for nearly 300 videos since 2007, has three books and a calendar, among other swag for sale. The squishy-faced, often blissed-out Scottish fold loves boxes and bags.

Not to be outdone, Simon’s Cat, a funny feline in a series of line-drawn animated videos out of London, has a book and an online store, as does Henri, who lends his fame and some of his dollars to cat charities.

So why cats?

Cats are fluffy and unpredictable and usually kept behind closed doors, which lends them allure and appeal that other common pets — I’m talking to you, dogs! — don’t seem to have when it comes to vapid, funny or deranged video. At least that’s what cat fans think.

“Cats are going to do what they want to do, and that’s one of the reasons that we love them,” said David Kargas, a Fresh Step spokesman who worked on Catdance.